Ferroelectricity in the xAg2Nb4O11–(1−x)Na2Nb4O11 solid solution

Compositions in the (AgxNa1-x)2Nb4O11 solid solution have been prepared by a conventional solid state method. Composites containing Ag2Nb4O11 have been shown to be ferroelectric and the Curie temperature shown to decrease from 149 °C at x = 1 to 62 °C at x = 0.7. Roomtemperature compositions with x ≤ 0.7 are monoclinic, while those with x ≥ 0.8 are rhombohedral with structures consistent with the relevant end-members. At x = 0.75, the structure was mainly rhombohedral but with coexistence of the monoclinic structure, indicating the proximity of a phase boundary

HRXRD study of the theoretical densities of novel reactive sintered boride candidate neutron shielding materials

Reactive Sintered Borides (RSBs) are novel borocarbide materials derived from FeCr-based cemented tungsten (FeCr-cWCs) show considerable promise as compact radiation armour for proposed spherical tokamak,[1],[2],[3],[4],[5]. Six candidate compositions (four RSBs, two cWCs) were evaluated by high-resolution X-ray diffraction (XRD), inductively coupled plasma (ICP), energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) to determine the atomic composition, phase presence, and theoretical density. RSB compositions were evaluated with initial boron contents equivalent to 25 at% 30 at%. All RSB compositions showed delamination and carbon enrichment in the bulk relative to the surface, consistent with non-optimal binder removal and insufficient sintering time. Phase abundance within RSBs derived from powder XRD was dominated by iron tungsten borides (FeWB/FeW2B2), tungsten borides (W2B5/WB) and iron borides. The most optimal RSB composition (B5T522W) with respect to physical properties and highest ρ/ρtheo had ρtheo = 12.59 ± 0.01 g cm-3 for ρ/ρtheo = 99.3% and had the weigh-in and post-sintered W : B : Fe abundance closest to 1 : 1 : 1. This work indicates that despite their novelty, RSB materials can be optimized and in principle be processed using existing cWC processing routes

Partial Hamiltonian reduction of relativistic extended objects in light-cone gauge

The elimination of the non-transversal field in the standard light-cone formulation of higher-dimensional extended objects is formulated as a Hamiltonian reduction.Comment: 11 page

Victimhood & Agency: How Taking Charge Takes Its Toll

This Article addresses an unexplored tension in the civil justice system regarding victims. The goal of the civil system is to make victims whole. We can, as is most common, attempt to do this financially, or we can consider psychological research that suggests there may be other ways of restoring victims’ statuses. One of the most common nonfinancial solutions is to increase victim participation in the justice process. This is a solution that appeals to many victims and may benefit them psychologically. However, by increasing their participation, they may unknowingly trade off some of the benefits of victimhood. For instance, they may be awarded less financial compensation and may even be blamed more for their own victimization. Part II of this Article discusses financial and nonfinancial strategies for making victims whole in the civil justice system. Part III addresses the paradoxical nature of victimhood in this system, and Part IV suggests that the psychological construct of agency may shed light on the issues victims face. Part V presents three empirical studies suggesting there are unanticipated consequences for victims who play an active role in the justice process, which may have serious ramifications for their recovery. The Article concludes with a discussion of the policy implications of these results, the limitations of the current studies, and future directions for this line of research

Structures of K0.05Na0.95NbO3 (50–300 K) and K0.30Na0.70NbO3 (100–200 K)

Rietveld refinement using neutron powder diffraction data is reported for the potential lead-free piezoelectric material KxNa1 - xNbO3 (x = 0.05, x = 0.3) at low temperatures. The structures were determined to be of rhombohedral symmetry, space group R3c, with the tilt system a-a-a- for both compositions. It was found that some of the structural parameters differ significantly in the two structures, and particularly the NbO6 octahedral strains as a function of temperature. The 300 K profile for K0.05Na0.95NbO3 shows the coexistence of rhombohedral and monoclinic phases, which indicates that the phase boundary is close to room temperature; the phase boundary for K0.30Na0.70NbO3 is found to be at approximately 180 K

Disability Awareness Course Outline using the Torrence Incubation Model (TIM)

Developing an Undergraduate Course Outline on Disability Awareness This project guides the reader through the process of creating an undergraduate course exploring disability history and the need for inclusion in society. The Torrance Incubation Model (TIM) was used to create the course outline which includes the course description, outcomes, competencies, assessment of student learning, and a topical outline. This project is twofold, and may be used as a stepping stones for training Direct Support Professionals by intertwining New York State’s Core Competencies within the course content and objectives

Bifurcated polarization rotation in bismuth-based piezoelectrics

ABO3 perovskite-type solid solutions display a large variety of structural and physical properties, which can be tuned by chemical composition or external parameters such as temperature, pressure, strain, electric, or magnetic fields. Some solid solutions show remarkably enhanced physical properties including colossal magnetoresistance or giant piezoelectricity. It has been recognized that structural distortions, competing on the local level, are key to understanding and tuning these remarkable properties, yet, it remains a challenge to experimentally observe such local structural details. Here, from neutron pair-distribution analysis, a temperature-dependent 3D atomic-level model of the lead-free piezoelectric perovskite Na0.5Bi0.5TiO3 (NBT) is reported. The statistical analysis of this model shows how local distortions compete, how this competition develops with temperature, and, in particular, how different polar displacements of Bi3+ cations coexist as a bifurcated polarization, highlighting the interest of Bi-based materials in the search for new lead-free piezoelectrics

Human Microsporidial Infections

Microsporidia are eukaryotic, spore forming obligate intracellular parasites, first recognised over 100 years ago. Microsporidia are becoming increasingly recognised as infectious pathogens causing intestinal and extra-intestinal diseases in both immuno-competent and immuno-suppressed patients. They are characterised by the production of resistant spores that vary in size depending on the species; and poses a unique organelle, the polar tubule (polar filament), which is coiled inside the spore as demonstrated by its ultra structure. Other unusual characteristics are the lack of mitochondria and the prokaryotic-like ribosomes, which indicate the primitive nature of the group. Presently there are seven genera, Enterocytozoon, Encephalitozoon, Nosema, Pleistophora, Trachi pleistophora, Brachiola, vittaforma species which have been reported from human hosts as agents of systemic, ocular, intestinal and muscular infections, are described and the diagnosis, treatment, and source of infections discussed

First detection of intestinal microsporidia in Northern Nigeria

Microsporidia are intracellular spore-forming protozoa that are increasingly being recognized as pathogens in humans. Faecal samples were taken from 2250 HIV/AIDS and 1050 HIV-negative patients from Kano and Makurdi in Northern Nigeria, and were investigated for microsporidial infections by Giemsa staining technique (Light microscopy). In Kano, Enterocytozoon bienuesi was detected in 8 (14.17%) and Encephalitozoon intestinalis in 5 (2.60%) out of 192 HIV/AIDS patients screened. A mixed infection of both 0.52% was observed. Results from Makurdi showed that Enterocytozoon bienuesi was detected in 13 (0.65%) and Encephalitozoon intestinalis in 96 (4.78%) out of 2008 HIV/AIDS patients examined. No mixed infection was observed. Microsporidial spores were not found in 1050 HIV-negative patients screened from both areas. There was a significant difference (X2, p<0.05) in infection rates between the HIV/AIDS and HIV-negative patients. This study aimed at detecting the prevalence of intestinal microsporidia to provide baseline data on the status of this disease in Nigeria. Detection of Microsporidia in Immuno-compromised patients has not been described previously in this area

Policy responses to invasive native species: issues of social and private benefits and costs

Farm and catchment managers in Australia face decisions about controlling invasive native species (or scrub) which may infest agricultural land. The treatment of this land to remove the infestation and re-establish native pastures is likely to be expensive for landholders. Yet there are potential social benefits from such remediation and so a policy question arises of what to do to about facilitating such change. New South Wales state government legislation addresses this issue through regulations, and the Catchment Management Authorities are responsible for administering public funds to achieve associated natural resource improvements. However, the extent of the private costs and social benefits associated with such changes are not known, which precludes benefit-cost analyses using the traditional welfare economics framework. This paper reports results of a social and private economic analysis of the impacts of a typical infestation remediation decision. We show that for the landholder the private costs exceed the benefits achieved from increased livestock productivity. However, there are social benefits expressed by the willingness to pay by members of the local catchment community for improvements in native vegetation and biodiversity. When these social benefits are included, the economic analysis shows a positive social net benefit. This raises questions of how to reconcile the public and private accounting, and whether any changes to policies, regulations or procedures for natural resource management in New South Wales are warranted.Invasive native scrub, environmental values, choice modelling, financial, economic, Namoi catchment,